Musculoskeletal (MS) ultrasonography (US) offers an overall assessment of the joints in OA. MSUS of the peripheral joints can be carried out at the time of consultation with high patient acceptability. This allows an immediate correlation between imaging findings and clinical data that improves diagnosis and management of patients with OA. The principal indications for MSUS in OA include detection of articular cartilage damage, bone changes, joint inflammation and adjacent soft tissue lesions. The main added value of US over clinical examination and plain radiography is its higher sensitivity for detecting synovitis and bone surface abnormalities, respectively. In addition, MSUS can be routinely used to guide accurate and safe diagnostic or therapeutic injections in the OA joints. The objective of the article is to describe the current applications of MSUS in both clinical practice and research in OA.